The present invention relates to a computerized method for simulating a multiphase flow of a plastic material and a gas, which is helpful to analyze fluidized states of a plastic material such as uncured rubber, resin and the like kneaded in a chamber.
In recent years, various computerized simulation methods have been proposed. For example, the following non-patent document 1 proposed a method to compute fluidized states of a plastic material such as uncured rubber or resin before cross-linked when kneaded in a banbury mixer.
[non-patent document 1] “Numerical and Experimental study of Dispersive mixing of Agglomerates”, V. Collin (1)*, E. Peuvrel-Disdier (1) et al.
The method of the non-patent document 1 is premised on that the chamber is completely filled with the plastic material (namely, filling rate=100%).
However, it is extraordinary to make kneading with the filling rate of 100% by the use of the banbury mixer or the like, and it has been known that with the change in the filling rate, the quality and state of the kneaded plastic material are altered.
Despite these facts, the method of the non-patent document 1 can not be performed by setting the filling rate of the plastic material at different values than 100%. Indeed, it is almost impossible to make the kneading with the filling rate of 100%, therefore, the simulation results of the non-patent document 1 can not be verified through experiments.
On the other hand, the viscosity of a plastic material is largely different from the viscosity of air, therefore, if a two-phase of a plastic material and air in a chamber is simulated by making a flow calculation, the calculation tends to become unstable. In the case that the flow calculation is made by the use of the actual viscosity of the air, even if the calculation is completed without being interrupted, the computational time becomes very long and a high computational cost is required.